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authorBharat Mediratta <bharat@menalto.com>2009-05-27 15:11:53 -0700
committerBharat Mediratta <bharat@menalto.com>2009-05-27 15:11:53 -0700
commit12fe58d997d2066dc362fd393a18b4e5da190513 (patch)
tree3ad8e5afb77829e1541ec96d86785760d65c04ac /system/libraries/drivers/Cache/Memcache.php
parent00f47d4ddddcd1902db817018dd79ac01bcc8e82 (diff)
Rename 'kohana' to 'system' to conform to the Kohana filesystem layout. I'm comfortable with us not clearly drawing the distinction about the fact that it's Kohana.
Diffstat (limited to 'system/libraries/drivers/Cache/Memcache.php')
-rw-r--r--system/libraries/drivers/Cache/Memcache.php191
1 files changed, 191 insertions, 0 deletions
diff --git a/system/libraries/drivers/Cache/Memcache.php b/system/libraries/drivers/Cache/Memcache.php
new file mode 100644
index 00000000..d801de9c
--- /dev/null
+++ b/system/libraries/drivers/Cache/Memcache.php
@@ -0,0 +1,191 @@
+<?php defined('SYSPATH') OR die('No direct access allowed.');
+/**
+ * Memcache-based Cache driver.
+ *
+ * $Id: Memcache.php 4102 2009-03-19 12:55:54Z Shadowhand $
+ *
+ * @package Cache
+ * @author Kohana Team
+ * @copyright (c) 2007-2008 Kohana Team
+ * @license http://kohanaphp.com/license.html
+ */
+class Cache_Memcache_Driver implements Cache_Driver {
+
+ const TAGS_KEY = 'memcache_tags_array';
+
+ // Cache backend object and flags
+ protected $backend;
+ protected $flags;
+
+ // Tags array
+ protected static $tags;
+
+ // Have the tags been changed?
+ protected static $tags_changed = FALSE;
+
+ public function __construct()
+ {
+ if ( ! extension_loaded('memcache'))
+ throw new Kohana_Exception('cache.extension_not_loaded', 'memcache');
+
+ $this->backend = new Memcache;
+ $this->flags = Kohana::config('cache_memcache.compression') ? MEMCACHE_COMPRESSED : FALSE;
+
+ $servers = Kohana::config('cache_memcache.servers');
+
+ foreach ($servers as $server)
+ {
+ // Make sure all required keys are set
+ $server += array('host' => '127.0.0.1', 'port' => 11211, 'persistent' => FALSE);
+
+ // Add the server to the pool
+ $this->backend->addServer($server['host'], $server['port'], (bool) $server['persistent'])
+ or Kohana::log('error', 'Cache: Connection failed: '.$server['host']);
+ }
+
+ // Load tags
+ self::$tags = $this->backend->get(self::TAGS_KEY);
+
+ if ( ! is_array(self::$tags))
+ {
+ // Create a new tags array
+ self::$tags = array();
+
+ // Tags have been created
+ self::$tags_changed = TRUE;
+ }
+ }
+
+ public function __destruct()
+ {
+ if (self::$tags_changed === TRUE)
+ {
+ // Save the tags
+ $this->backend->set(self::TAGS_KEY, self::$tags, $this->flags, 0);
+
+ // Tags are now unchanged
+ self::$tags_changed = FALSE;
+ }
+ }
+
+ public function find($tag)
+ {
+ if (isset(self::$tags[$tag]) AND $results = $this->backend->get(self::$tags[$tag]))
+ {
+ // Return all the found caches
+ return $results;
+ }
+ else
+ {
+ // No matching tags
+ return array();
+ }
+ }
+
+ public function get($id)
+ {
+ return (($return = $this->backend->get($id)) === FALSE) ? NULL : $return;
+ }
+
+ public function set($id, $data, array $tags = NULL, $lifetime)
+ {
+ if ( ! empty($tags))
+ {
+ // Tags will be changed
+ self::$tags_changed = TRUE;
+
+ foreach ($tags as $tag)
+ {
+ // Add the id to each tag
+ self::$tags[$tag][$id] = $id;
+ }
+ }
+
+ if ($lifetime !== 0)
+ {
+ // Memcache driver expects unix timestamp
+ $lifetime += time();
+ }
+
+ // Set a new value
+ return $this->backend->set($id, $data, $this->flags, $lifetime);
+ }
+
+ public function delete($id, $tag = FALSE)
+ {
+ // Tags will be changed
+ self::$tags_changed = TRUE;
+
+ if ($id === TRUE)
+ {
+ if ($status = $this->backend->flush())
+ {
+ // Remove all tags, all items have been deleted
+ self::$tags = array();
+
+ // We must sleep after flushing, or overwriting will not work!
+ // @see http://php.net/manual/en/function.memcache-flush.php#81420
+ sleep(1);
+ }
+
+ return $status;
+ }
+ elseif ($tag === TRUE)
+ {
+ if (isset(self::$tags[$id]))
+ {
+ foreach (self::$tags[$id] as $_id)
+ {
+ // Delete each id in the tag
+ $this->backend->delete($_id);
+ }
+
+ // Delete the tag
+ unset(self::$tags[$id]);
+ }
+
+ return TRUE;
+ }
+ else
+ {
+ foreach (self::$tags as $tag => $_ids)
+ {
+ if (isset(self::$tags[$tag][$id]))
+ {
+ // Remove the id from the tags
+ unset(self::$tags[$tag][$id]);
+ }
+ }
+
+ return $this->backend->delete($id);
+ }
+ }
+
+ public function delete_expired()
+ {
+ // Tags will be changed
+ self::$tags_changed = TRUE;
+
+ foreach (self::$tags as $tag => $_ids)
+ {
+ foreach ($_ids as $id)
+ {
+ if ( ! $this->backend->get($id))
+ {
+ // This id has disappeared, delete it from the tags
+ unset(self::$tags[$tag][$id]);
+ }
+ }
+
+ if (empty(self::$tags[$tag]))
+ {
+ // The tag no longer has any valid ids
+ unset(self::$tags[$tag]);
+ }
+ }
+
+ // Memcache handles garbage collection internally
+ return TRUE;
+ }
+
+} // End Cache Memcache Driver